The invention concerns an overhead projector.
A prior-art overhead projector comprises:                a screen equipped with a frame and a translucent panel tautened on this frame, the translucent panel having a front face on which the images are displayed and a rear face on which the images are projected, and        an apparatus for projecting images on the rear face of the translucent panel.        
The term “overhead projector” herein designates apparatuses in which the image becomes directly visible to the spectator after having crossed the translucent panel. These overhead projectors are different from apparatuses in which the image is projected on an opaque screen. Indeed, in the latter case, the projected image can be seen by the spectator only after it has been reflected on the opaque screen.
Here, the term “translucent panel” designates a panel which disseminates, on its front face side, the image projected on its rear face so as to make it directly perceptible to a human being placed before this panel. To this end for example, the panel has agents scattering light such as to prompt an angular aperture of the light beam projected on its rear face when this beam crosses the panel. This angular aperture of this beam is for example prompted by multiple diffractions.
There are numerous applications for overhead projectors. For example, the overhead projectors are used as a television set.
These overhead projectors may have a large screen, which is appreciated by users. The trade-off is that the large size of the screen makes the overhead projector difficult to transport.